1. Field of the Invention
The present invention relates to a method of forming a coat on an inner surface of a bearing having a cylinder shape and an apparatus for forming the coat.
2. Description of the Prior Art
Conventionally, for the purpose of improving conformability and anti-seizure property, a synthetic resin coat has been formed on an inner surface of a half bearing having a semi-cylinder shape, for example. The coat often includes a base resin made of a synthetic resin in which a solid lubricant is contained. As a method of forming such a coat, there have been known a plurality of methods as follows.
(1. Air Spray Method)
As shown in FIG. 4, in the case of a half bearing for example, while two half bearings 101 are held by a jig (not shown) to be combined into a cylinder shape and while the bearings 101 are rotated in their circumferential direction together with the jig, a coating material 103 (a mixture of a base resin and a solid lubricant) for forming a coat is injected from diagonally above the bearings 101 (approximately at 45 degree from above the bearings 101) toward an inner surface of each bearing 101 using a nozzle 102 by the air spray method, to apply the coating material thereon. Then, the jig is turned upside down, and the coating material is applied also from the opposite side in the same manner. Thereafter, the base resin is cured.
(2. Printing Method)
A coating material for forming a coat is applied on a printing surface of a pad, then the printing surface is pressed onto an inner surface of a bearing to transfer the coating material thereon. Thereafter, the coating material is cured.
(3. Immersion Method)
A bearing is directly immersed in a coating material to deposit the coating material on an inner surface of the bearing, and then the bearing is drawn from the coating material and undergoes curing.
(4. Roll Coat Method)
A coating material for forming a coat is dropped on a transfer roll, and the transfer roll and a printing roll are rotatably contacted with each other to transfer the coating material on the printing roll. Then, a bearing (a back plate) having a semi-cylinder shape is engaged between the printing roll and a backup roll such that an inner surface of the bearing contacts with the printing roll to apply the coating material on the inner surface of the bearing. Thereafter, the coating material is cured (see page 4 and FIGS. 2 and 3 of JP-A-2001-304264, for example).